7. D

8. A

***

1. New deviced have been invented to help people live a longer life by scientists. 

2. If they revise them all hard, they will do the test well. 

3. The villagers in the raged flood have been evacuted to the safe place by the resuce workers last night. 

4. Aids will be provided to the homeless people by the students tomorrow. 

5. If people protect the enviroment now, the enviroment will be nice. 

6. If they had a map, they wouldn't get lost. 

7. Many houses in this village were destroyed by the storm last week. 

8. Was food fiven to the homeless people last year? 

9. Despite the bad weather, the football match was not cancelled. 

10. Many rivers and lakes are poisoned because fatories produce waste and pủ it into lakes and rivers. 

11. Plastic bags are a major source of waste so we shouldn't throw plastic bags everywhere. 

12. If it didn't cost too much money, we would hold the festival. 

13. The tortoise was running while the hare was sleeping. 

14. Although the girl worked hard, her stepmother wasn't happy. 

15. Because of being sich, Peter didn't go to school yesterday.